fix: escape sequences in search output (#687)

Fix an issue whereby ANSI escape characters could appear in search
output when a pager was not configured.

The root cause of the problem was code that was overzealously applying
an underlying effect to search terms.

This commit simply rips out underlying entirely, both as means of
resolving this problem, and also simply for removing needless visual
noise from search output.

cmd/cheat/cmd_view.go

@@ -41,7 +41,7 @@ func cmdView(opts map[string]interface{}, conf config.Config) {
 
 				// identify the matching cheatsheet
 				out += fmt.Sprintf("%s %s\n",
-					display.Underline(sheet.Title),
+					sheet.Title,
 					display.Faint(fmt.Sprintf("(%s)", sheet.CheatPath), conf),
 				)